.TH LCTL-DEL_OST 8 2024-08-13 Lustre "Lustre Configuration Utilities"
.SH NAME
lctl-del_ost \- permanently delete OST records
.SH SYNOPSIS
.SY "lctl del_ost"
.RB [ --dryrun ]
.B --target
.I OST_LABEL
.YS
.SH DESCRIPTION
.B lctl del_ost
cancels the config records for an OST specified by
.I OST_LABEL
to permanently forget about it. It should be run on the MGS and will
search for the specified OST in the Lustre configuration log files for
all MDTs and clients. If
.B --dryrun
is not specified, it will modify the configuration log files to
permanently disable the OST records. Newly mounted MDTs and clients
will not process deleted OSTs anymore. This method allows to permanently
remove OSTs on a live filesystem without the use of --writeconf with
.BR tunefs.lustre (8).
.P
Before using this command, you probably want to migrate
file objects still on the OST by using
.BR lfs-migrate (1)
or
.BR lfs_migrate (1)
and make sure that there are no remaining file objects on the
OST by using
.BR lfs-find (1)
which can find files by OST index.
It is then recommended to first deactivate the OST using
.BR lctl (8)
with:
.RS 8
.B # lctl conf_param lustre-OST0001.osc.active=0
.RE
and finally use
.B lctl del_ost
to remove it from the configuration logs.
.SH OPTIONS
.TP
.BR -n ", " --dryrun
An option provided so that the system administrator can see which
records would have been cancelled, but without actually cancelling them.
When deleting OST records, it is recommended to first use this option
and check that there are no errors.
.TP
.BR -t ", " --target
This option is required and used to specify the OST label to permanently
delete from the records. The target label should be of the form
.BR "fsname-OST0a19" .
.SH EXAMPLES
.EX
.B # lctl --device MGS del_ost --target lustre-OST0001
.EE
.SH AVAILABILITY
.B lctl del_ost
is a subcommand of
.BR lctl (8)
and is distributed as part of the
.BR lustre (7)
filesystem package since release 2.11.0
.\" Added in commit v2_10_55_0-41-gd62efba975
.SH SEE ALSO
.BR lfs-find (1),
.BR lfs-migrate (1),
.BR lfs_migrate (1),
.BR lustre (7),
.BR lctl (8),
.BR lctl-llog_cancel (8),
.BR tunefs.lustre (8),
